1. Field of the Invention
This invention relates to luminescent particles and, in particular, to luminescent polymeric micro- and nanoparticles, as well as methods of making and using such particles.
2. Description of the Related Art
There is a high demand for chemical sensor devices for detecting low concentration levels of analytes present in the liquid and gaseous phase. Specificity to particular analytes is also generally desired.
Chemical sensor devices often involve luminescent materials because luminescence lifetimes and intensities can be sensitive to the presence of external species or analytes. Luminescent polymeric materials are particularly advantageous for sensor devices because the resulting luminescence and other physical properties can be optimized and/or tailored for particular analytes through chemical structure changes of the polymer.
Luminescent polyelectrolytes such as poly(phenylene)s or poly(phenylene vinylene)s have been described in, for example, Harrison et al., J. Am. Chem. Soc., 122: 8561(2000); Gaylord et al., J. Am. Chem. Soc., ASA Release.
Other polymeric particles have been disclosed in for example, Zhang et al., Acct. Chem. Res. ASA Release; Lei et al., Marcomolecules, 30: 2201-2203 (1997); and Hoger, et al., J. Am. Chem. Soc. ASA Release. Additionally, patents that disclose particles include, for example, Haugland et al., U.S. Pat. No. 5,723,218; Fischer et al., U.S. Pat. No. 5,710,197; Ricchiero et al., U.S. Pat. No. 5,607,864; or Scoennert et al., U.S. Pat. No. 5,591,787. Fluorescent particles can be used, for example, as a substrate to attach molecules to, or as a label or tracer to detect various molecules, such as in a biological system or in a chemical assay. Fluorescent particles have also been used for diagnostic tests due to their size and ease of detection. Many different techniques can be used to detect particles, such as ordinary light or fluorescence microscopy, laser scanning confocal microscopy, or fluorescence spectroscopy and related techniques.